WASHINGTON -- Congressional Republicans acknowledged their options are limited in replacing Obamacare, though they vowed that Thursday's U.S. Supreme Court decision upholding federal subsidies is not the end of their fight.

"You deal with the rules that you have," said House Budget Committee chairman Tom Price (R-Ga.). "And now, the rules won't let you do everything you wanted to do."

Republican presidential candidates added their voices to calls to scrap the law, though they didn't say how they'd do so. One of them, former Florida Gov. Jeb Bush, said, "This decision is not the end of the fight against Obamacare."

Bush quickly cited the court decision in a fundraising appeal. "That is why I need you to make a one-time emergency contribution of $50, $25 or $10 to my campaign," the email said.

Democratic presidential candidate Hillary Rodham Clinton said, "Anyone seeking to lead our country should stand up and support this decision."

A Twitter link directed supporters to Clinton's campaign website and encouraged them to provide their email address and ZIP code to "Stand with Hillary for health care."

Even if the Republican-led House and Senate were able to pass legislation repealing the health care law, Obama would veto it and Democrats would provide enough votes to sustain a veto. The House has already voted more than 50 times to repeal all or part of it.

Joseph Antos, a health policy expert at the American Enterprise Institute, a group that supports limited government, said of the Supreme Court ruling: "Because this is such a strong decision and endorsement of the Democrats' stand on this, it makes it even less likely that Republicans could pass any kind of legislation changing anything about the Affordable Care Act."

Democrats in Congress said the court ruling is a signal to Republicans to stop fighting the law.

"Stop wasting the time of the American people by trying to repeal a law," said Senate Minority Leader Harry Reid, a Nevada Democrat. "Enough's enough. Let's move on."

Rep. Paul Ryan (R-Wis.), chairman of the House Ways and Means Committee, had been working on a plan in case the court ruled against the law.

Ryan said his committee "will continue its work to advance a patient-centered alternative to finally repeal and replace Obamacare."

Senate Majority Leader Mitch McConnell, a Kentucky Republican, urged Democrats to work with Republicans to alter the law, which he called "a rolling disaster," to mitigate what some Republicans say are adverse impacts on the American public.

"The politicians who forced Obamacare on the American people now have a choice: crow about Obamacare's latest wobble towards the edge, or work with us to address the ongoing negative impact," McConnell said in a floor speech.